Staffordshire HS2 protesters tunnel underground in camp
Protesters opposing HS2 have set up a third camp in Staffordshire just over a week since evictions began at an encampment near Swynnerton.
Campaigners demonstrating against plans to cut down woods for the line have tunnelled underground where they hope it will be harder for security teams to reach them but there are concerns over air quality.
Protester Jim Knaggs said "bailiffs aren't allowing" air to come through and added "it's just a basic humanitarian issue to give people air".
HS2 have deployed their own tunnelling team and said safety is their first priority. They have provided protesters with a system of communication in the event of an emergency.
A spokesperson said: "We continue to urge the protesters who are unlawfully encamped on this land to leave their tunnel immediately, which they are free to do at any time.
"Until they do, our tunnelling team is regularly using digital air quality monitoring equipment to ensure that the quality of the tunnel atmosphere is maintained, and they periodically pump in fresh air if needed."